Ski



FIG. 1 is a top perspective view of a ski, showing my new design;

FIG. 2 is a bottom perspective view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof; and,

FIG. 5 is a side elevational view thereof, the side opposite being a mirror image. 

The ornamental design for a ski, as shown and described. 